Apparatus for severing an axially moving rod into lengths



Dec. 20, 1938. FER A W 2,140,720

APPARATUS FOR SEVERING AN AXIALLY MOVING ROD INTO LENGTHS Filed Nov. 27,1936 Patented Dec. 20, 1938 UNITED STATES PATENT OFFIQE APPARATUS FORSEVERING AN AXIALLY' MOVING ROD INTO LENGTHS London, England ApplicationNovember 27, 1936, Serial No. 113,053

In Great Britain December 17, 1935 13 Claims.

This invention is for improvements in or relating to apparatus forsevering an axially moving rod into lengths.

The invention is primarily intended for use with cigarette makingmachines of the continuous rod type, in which case the severing devicemay comprise a rotatable circular disc knife or a sickle shaped knife,but it may also be applied to other purposes by substituting an abrasivecutter (e. g., a wheel) or other cutter for the knife which is used whencutt'mg a cigarette rod. For convenience the term knife will be usedthroughout for all types of cutter.

In order to eifect satisfactory severing or cutting of a moving rod, itis necessary that the knife shall have two movements, or the equivalentthereof, namely, translation of the knife parallel to its own plane inthe direction in and at substantially the same speed at which the rod isI moving, and an edgewise movement of the knife towards the rod in orderto effect the cutting, and where a rotatable knife is used the thirdmovement, namely, rotation ofthe knife disc.

The present invention provides improved means for giving the knife thenecessary movements whereby the knife passes through an orbit which ispreferably of circular or elliptical shape. The shape of the orbit isdetermined by the amplitude and relative velocity of the two first saidmovements which may be combined in a single rotary movement where acircular orbit is desired.

According to one form of the present invention there is provided acutting mechanism comprising in combination a support, a member anchoredthereto by universal joint (e. g. a Hookes joint), a knife carrierpivoted to said member to swing in one plane only relatively to saidmember, means to impart to the member an orbital movement in such mannerthat a line joining the centre of the universal joint and the-axis ofthe carrier pivot sweeps out a conical surface, whilst the axis of thecarrier pivot is maintained 45 parallel to its initial position, a knifeon the knife carrier and means to maintain the carrier or the carrierand the knife at all times parallel to a given plane (e. g. a planenormal to a continuously moving rod which is to be severed).

The means for maintaining the knife parallel may comprise a secondmember mounted to have the same movement as the first said member andconnected to the knife carrier by a pivot which is parallel to the firstsaid carrier pivot in such manner'that the centres of the universaljoint and axes of the pivots are at the corners of a parallelogram.

The distance between the knife and centre of the universal joint isdifferent from the distance between the pivot and the universal joint onthe 5 member or members whereby the knife is movable through an orbit ofelliptical shape.

Further; according to the present invention, there'is provided a cuttingmechanism comprising a knife mounted on a carrier, a pivoted mem- 10 bermounted to sweep out a conical surface of revolution, and connected tothe knife carrier, whereby the knife is caused to traverse an orbit, andmeans for maintaining the knife in parallel planes at all times (e. g.normal to the axis of 5 the moving rod during the movement of the knifethrough the orbit). The member may be arranged as a lever of the firstorder in which case it generates two conical surfaces of revolution.

Again, according to the present invention there is provided a cuttingmechanism comprising a knife mounted on a carrier connected by pivotedlinks to a member, said knife being disposed at a distance from themember diiferent from that of the line joining the carrier pivots, thecarrier, links and member together forming a parallelogram, said memberin turn being pivotally mounted for oscillation about an axis at rightangles to the link pivots, a lever pivoted to said member at a point onits axis and operatively 30 connected to the parallel links and driventhrough a circular path at one end whereby a conical movement isimparted to the lever and the knife is moved through an orbit ofelliptical shape.

In all cases means may be provided for rotating the knife on its axiswhen required.

The invention will be described by way of example with reference to theaccompanying drawing in which Figure l is a side elevation partly insection of cutting mechanism for cutting a continuous cigarette rod.

Figure 2 is a plan of a part of Figure 1.

Like references refer to like parts throughout the specification anddrawing.

With reference to the drawing, a circular knife 5 is mounted on aspindle 5 carried in bearings l which are attached to bracket 8. Thebracket 8 is secured by bolts 30 to a carrier 3| which is adapted toform one link of a paral el link mechanism. The bearings I, bracket 8and carrier 3| combined will be referred to hereinafter as the knifecarrier. v

The carrier 3| is pivoted at 9 and It] to two parallel links H and I2which are themselves pivoted at I3 and I4 respectively to a supportshown as a shaft I5 so that the four pieces together form a jointedparallelogram. The shaft I5 to which the parallel links II and I2 arepivoted is rotatable in bearings Iii formed in a bracket I? attached tothe bed of the cigarette machine. The axes of the pivots I3 and I4 ofthe links II and I2 to the shaft intersect the axis of the latter thusforming two Hookes joints or universal joints, and the parts are sodisposed that the axis of the shaft I lies parallel to the direction ofmovement of the cigarette rod and the axis of the circular knife 5 isalso parallel to the cigarette rod. It will be seen from Figure 2 thatthe distance between the axis of rotation of the knife 5 and the centresI3 and I4 of the universal joints is greater than the distance from thecentres of the joints I3 and I4 to the pivots 9 and ID of the links I Iand I2 to the knife carrier. 7

The cigarette rod is passed through a ledger tube 35 which moves withthe cigarette rod during the cutting operation, in the usual manner.

The link I2 has an extension I8 beyond the pivot I4 which attaches it tothe shaft 1, and this extension is coupled to a crank disc IS in such amanner that when the disc is rotated the extension I8 of the link I2sweeps out a conical surface, the centre point of the pivot I4 being theapex of the cone. The link I2 thus forms a lever of the first order.

The crank disc I9 is mounted on a shaft 20, and the end of the extensionI8 fits in a ball race 2| fixed on the crank disc I9.

It will be seen that that part of the link I2 which is disposed betweenthe pivots I0 and I4 also sweeps out a cone.

The shaft 29 is rotated by gearing 33 and 34 driven from the main driveof the cigarette making machine.

When the apparatus is working the throw of the knife 5 in a plane atright angles to the axis of the shaft I5 is greater'than the throw inthe direction of the shaft. In cigarette machines as usually constructedthe cigarette rod is horizontal, and as previously stated, the shaft I5is supported parallel to the cigarette'rod. Consequently, the orbit ofthe knife 5 is an ellipse with the major axis substantially vertical andthe proportion of the major axis to the minor axis may be increased ordecreased by decreasing or increasing respectively the length of thelink I2 relatively to the distance of the knife 5 from the axis of theshaft I5.

The mechanism thus gives a translation of the knife parallel to itselfand by suitably proportioning the parts the knife may be arranged totravel at the desired speed during the cutting operation, and as it isdesirable that the cutting should be effected in the shortest possibletime, the ellipse referred to is made relatively flat and the cuttingoperation takes place while the knife is passing through one of theextremities of the ellipse of smallest curvature, i. e., a portion ofthe curve near to a focus.

The edgewise movement of the knife 5 is naturally obtained owing to thefact that as the knife sweeps through its elliptical orbit, the bottomedge of the knife dips towards and through the cigarette rod.

The mechanism for rotating the knife 5 on its spindle 6 may be of anydesired kind, but a simple and convenient device consists in mounting agrooved pulley' 22 on the end of the knife spindle 6 Opposite to that atwhich the knife 5 is located and driving this pulley by a belt 23running around a pulley 24 mounted at some suitable part of the machine.

As the belt 23 will be fairly long in comparison with the pulleydiameters, an ordinary leather belt will be suitable as the distancebetween the centres of the pulleys does not change appreciably, but ifdesired, an elastic belt may be used.

It is frequently necessary when operating a cigarette machine to changethe length of the knife throw in order to produce cigarettes of adifferent length, and in the present case this is accomplished byaltering the radius of the base of the cone swept out by the end of thelever which is connected to the crank disc.

A convenient way of effecting this is to make the face of the crankdiscI9 of concave spherical shape as shown in Figure 1 with a groove 25across the concave face passing through the centre thereof. The ballrace 2| is mounted in a block 26 slidable in the groove 25 and by thismeans the end of the lever may be moved to any desired point along thisgroove to alter the crank radius and fixed in the desired position. Theblock is secured in position after adjustment by bolts 21 and 28.

It will be appreciated that any suitable means may be provided tosharpen the knife, such means being well known in the art.

As will be seen from Figure 1, the bottom of the bracket 8 is providedwith serrations 32 which co-operate with similar serrations formed onthe carrier 3|. The purpose of this arrangement is to permit the knife 5to be adjusted to compensate for wear, for example, wear due to thegrind ing of the knife.

Where a sickle shaped knife (i. e. an eccentric edged knife) is used itmay be mounted on a disc for rotation, in which case the mechanism willbe similar to that already described, but in certain cases rotation maybe dispensed with providing that the angle of the sickle is steep enoughfor the knife to make a satisfactory cut by a shearing action.

What I claim as my invention and desire to secure by Letters Patent is:

1. A cutting mechanism comprising in combination a support, a memberanchored thereto by a universal joint,'a knife carrier pivoted to saidmember to swing in one plane only relatively to said member, means toimpart to the member an orbital movement in such manner that a linejoining the centre of the universal joint and the axis of thecarrierpivot sweeps out a conical surface, a knife on the knife carrierand means to maintain the knife at all times parallel to a given plane.

2. A cutting mechanism comprising a knife mounted on a-carrier, apivoted member mounted to sweep out a conical surface of revolution, andconnected to the knife carrier, whereby the knife is caused to traversean orbit, and means for maintaining the knife in parallel planes at alltimes.

3. A cutting mechanism comprising. a carrier, a knife mounted on thecarrier, a support, links connecting the carrier with the support,carrier pivots connecting the links with the carrier, link pivotsconnecting the links with the support, said knife being disposed at adistance from the support different from that of the line joining thecarrier pivots, the carrier, links and support together forming aparallelogram, said support in turn being journalled for oscillationabout an axis at right angles to the axes of said link pivots,

and a lever pivoted to said support, the pivotal axis of the leverintersecting the axis of the support, said lever being operativelyconnected to the parallel links and its extremity driven through acircular path whereby a conical movement is imparted to the lever andthe knife is moved 7 through an orbit of elliptical shape.

4. A cutting mechanism for severing a continuously moving rod comprisingin combination a support, a member anchored thereto by a univ-ersaljoint, a knife carrier pivoted to said member to swing in one plane onlyrelatively to said member, means to impart to the member an orbitalmovement in such manner that a line joining the centre of the universaljoint and the axis of the carrier pivot sweeps out a conical surface, aknife on the carrier, and means to maintain the knife at all timesparallel to a plane normal to the continuously moving rod.

5. A cutting mechanism for severing a continuously moving rod comprisinga knife mounted on a carrier, a pivoted member mounted to sweep out aconical surface of revolution and connected to the knife carrier,whereby the knife is caused to traverse an orbit, and means formaintaining the knife at all times in parallel planes which planes arenormal to the axis of the moving rod during the movement of the knifethrough the orbit.

6. A cutting mechanism comprising in combination a support, a lever ofthe first order anchored to the support by a universal joint, a knifecarrier pivoted to said lever to swing in one plane only-relatively tothe lever, means to impart to the lever an orbital movement in suchmanner that a line joining the centre of the universal joint and theaxis of the carrier pivot and extended beyond the centre of theuniversal joint sweeps out two conical surfaces of revolution, theapexes of the conical surfaces of revolution being coincident with thecentre of the universal joint, a knife on the knife carrier, and meansto maintain the knife at all times parallel to a given plane.

'7. A cutting mechanism comprising a knife mounted on a carrier, apivoted lever of the first order connected to the knife carrier andmounted to sweep out two conical surfaces of revolution, the apexes ofthe conical surfaces of revolution being coincident with the centre ofthe pivot of said lever, whereby the knife is caused to traverse anorbit, and means for maintaining the knife in parallel planes at alltimes.

8. A cutting mechanism comprising in combination a support, a memberanchored thereto by a universal joint, a knife carrier pivoted to saidmember to swing in one plane only relatively to said member, means toimpart to the member an orbital movement in such manner that a linejoining the centre of the universal joint and the axis of the carrierpivot sweeps out a conical surface, a knife on the knife carrier, and asecond member mounted to have the same movement as the first said memberand connected to the knife carrier by a pivot which is parallel to thefirst said carrier pivot in such manner that the centres of theuniversal joint and the axes of the pivots are at the corners of aparallelogram, whereby the knife is at all times maintained parallel toa given plane.

9. A cutting mechanism comprising in combination a support, a memberanchored thereto by a universal joint, a knife carrier pivoted to saidmember to swing in one plane only relatively to said member, means toimpart to the member an orbital movement in such manner that a linejoining the centre of the universal joint and the axis of the carrierpivot sweeps out a conical surface, a knife on the knife carrier, andmeans to maintain the knife at all times parallel to a given plane, thedistance between the knife and the centre of the universal joint beingdifferent from the distance between the pivot and the universal joint onthe member, whereby the knife is movable throughout an orbit ofelliptical shape.

10. A cutting mechanism comprising a circular knife journaled forrotation on a carrier, mechanism to rotate said knife about its axis, apivoted member mounted to sweep out a conical surface of revolution andconnected to the knife carrier, whereby the knife is caused to traversean orbit, and means for maintaining the knife in parallel planes at alltimes.

11. A cutting mechanism comprising a knife journalled for rotation on acarrier, mechanism to rotate the knife about its axis, pivotal linksconnecting said carrier to a support, said knife being disposed at adistance from the support different from that of the line joining thecarrier pivots, the carrier, links and support together forming aparallelogram, said support in turn being journalled for oscillationabout an axis at right angles to the link pivots, and a lever pivoted tosaid support, the pivotal axis of the lever intersecting the axis of thesupport, said lever being operatively connected to the parallel linksand its extremity driven through a circular path, whereby a conicalmovement is imparted to the lever and the knife is moved through anorbit of elliptical shape.

12. A cutting mechanism comprising in combination a support, a memberanchored thereto by a universal joint, a knife carrier pivoted to saidmember to swing in one plane only relatively to said member, means toimpart to the member an orbital movement in such manner that a linejoining the centre of the universal joint and the axis of the carrierpivot sweeps out a conical surface, a knife on the knife carrier, meansto maintain the knife at all times parallel to a given plane, and meansto move said knife relatively to the carrier to adjust the knife tocompensate the knife for wear.

13. A cutting mechanism comprising a knife mounted on a carrier, apivoted member mounted to sweep out a conical surface of revolution andconnected to the knife carrier, whereby the knife is caused to traversean orbit, means for maintaining the knife in parallel planes at alltimes, and means to move the knife relatively to the carrier to adjustthe knife to compensate the knife for wear.

FELIX FREDERIC RUAU.

